The invention relates to products and process(es) of production thereof in which waste asphalt shingles are converted into useful dimensional construction material including without limitation paving blocks as for walkways or patios or landscape borders for flower or shrub gardens, retaining wall blocks, bricks, tire stops, curbs, tiles, posts, beams and so on.
Asphalt roofing shingles, needless to say, are popular and in widespread use across this country on structures of all types in every region. What has to date not been a sensational or headline-worthy fact about asphalt roofing shingles is, that they are responsible for a massively voluminous waste stream.
The waste stream of asphalt roofing shingles is, generally speaking, fed by two sources. The majority of the waste shingle stream comprises spent shingles that are, e.g., tear-offs from re-roof jobs or demolition debris. Much of the remainder of the waste shingle stream comprises scrap of new shingles:--either the tabs that are cut out during shaping of completed shingles or discarded rejects that failed to pass quality standards.
The portion of the waste stream composed of new shingles contains fresh asphalt. The portion the waste stream composed of spent shingles as from, e.g., tear-offs, is likely to include a variety of contaminant debris such nails, swatches of roofing felt (e.g., an underlying and redundant vapor barrier), wood from the underlying substrate (e.g., plywood), perhaps some metallic strip material from flashing, and so on.
The disposal of spent asphalt shingles is regulated. Spent asphalt shingles must either be sent to a sanitary landfill or a more special purpose demolition landfill. For roofing contractors, there is a sub-economy involved in the disposal of spent shingles which must be dealt with and figured into the calculus of a roofing job because, if ignored, all of the time, money, and equipment tied-up in disposing the spent shingles can wipe out profit.
For example, consider this situation which presently exists in Springfield, Mo. After a roofing contractor has torn off a roof, he or she is now faced with disposal. The city landfill 10 miles north of the center of town accepts such debris, at a charge of $27.50 each ton. The contractor, depending on where the job site is, may actually have a longer trip to go than the 10 miles from the center of town. Also, the roofing contractor may be charged a surcharge for offloading if he or she cannot offload in accordance with the landfill's local policies. More significantly, there is usually a wait in a line before the landfill can service the contractor's load, and at times the wait can be significantly extended if the line is long. This waiting period is most frustrating because it idles manpower and truck(s) for the duration. This especially acute when, after a hailstorm or like roof-damaging weather event, a roofing contractor experiences a temporary bonanza in business. Provided, of course, that he or she does not squander much of this temporary bonanza away with an unnecessarily long commute to and from, or delay because of waiting at the landfill.
At least one containerized trash-hauler has reacted to the plight of the roofing contractors with a specialized service by which, the containerized trash-hauler has at least one centrally located transfer station where it will also accept the spent shingle debris:--at a premium charge naturally enough. The basic charge is $37.50 each ton, which excludes surcharges if help is needed offloading the debris and depositing it into the container(s).
Regardless of by which option the roofing contractor disposes of the spent shingles, the outcome for the spent shingles is the same:--the spent shingles are landfilled. It has been recognized by the inventors hereof that this stream of waste shingles presently being landfilled in this country, can be diverted to processing centers in accordance with the invention for conversion/recycling into useful products. Moreover, a processing center in accordance with the invention can be coordinated with one or more collection centers in accordance with the invention in order to (i) service the needs of roofing contractors (or whoever else finds themselves with waste shingles) by providing a conveniently located dump site, as well as (ii) service the processing center by obtaining a continuous supply of the feedstock (i.e., waste shingles) for the processing center.
A number of additional advantages and aspects of the invention will be apparent in connection with the following summary of the invention and discussion of preferred embodiments and examples.